The joys of living on the DNA cutting edge
It’s a bit disconcerting when your DNA tells you you’re … um … not you.
At least, The Legal Genealogist found it to be so this morning.
There’s a new Tier 1 utility, you see, at GEDmatch Genesis, that allows you to combine your DNA results from multiple testing companies into one super-duper-kit. The idea is that — although there’s a lot of overlap from company to company — the individual testing companies do look at somewhat different places in your autosomes for genealogically relevant markers. So, by combining results, you’d get a more complete set of markers than from any one test.
Think about it this way. Let’s say company A looks at your autosomal DNA — the kind of DNA used in the tests that help us compare our DNA to that of our biological cousins so we can work together to trace our family history1 — in places 1, 2, 3, 4, 5, 8, and 10. And company B looks at places 1, 2, 3, 4, 5, 6 and 7. And company C looks at places 1, 2, 3, 4, 5, 9, and 10. Adding those three kits together would give us a combined look at places 1-10. Pretty cool, huh?
Since I’ve tested with just about everybody under the sun, and I am a Tier 1 GEDmatch user,2 I figured it was worth trying it to see what if any differences there might be between the test results from individual companies and this kind of a super-kit. You can combine tests from four companies so I figured I’d combine results from 23andMe, AncestryDNA, Family Tree DNA and Living DNA.
I hadn’t previously uploaded some of these since I saw no reason to overload the GEDmatch system with that many kits for one person, so I went ahead and did that. And then figured I’d run one-to-one comparisons to make sure I had a good baseline — just what one company might have that another company doesn’t.
First up — looking just at Chromosome 1 — me at Ancestry versus me at 23andMe.
Yup, all that green says I’m me, all right. And the little breaks may suggest where one company has data and the other one doesn’t.3 A total of 621271 SNPs were used for the comparison,4 and 99.997 percent of the SNPs were fully identical.
Next up — again looking just at Chromosome 1 — me at Ancestry versus me at FTDNA.
Yup, still me, all right. This time 631,301 SNPs were used and 99.999 percent were fully identical.
Next up — still looking just at Chromosome 1 — me at Ancestry versus me at Living DNA.
Um… waitaminnit here. What’s with all that black???
The color code says it means that, comparing 162,427 SNPs… um … there’s no match. “No shared DNA segments found.”
I’m not me?
Okay… maybe it’s the default settings that are causing this. There are different builds — reference sets, called assemblies, issued by the Genome Reference Consortium5 — that can be reported. It was the default that says I’m not me in the graphic above.
So I re-ran it at each setting. The default, Build 37, says I’m not me. But Build 36 says I’m not me. And Build 38 — still not me.
Ditto for a one-to-one comparison between Living DNA and 23andMe. Ditto between Living DNA and Family Tree DNA.
Okay, maybe I downloaded the wrong kit from Living DNA. So I went back and downloaded it again and did a comparison of the files. File name? Check. File size? Check. File contents? Yet another check. No error there; it’s the kit that Living DNA thinks is me.
So… I’m me at three companies, and they all compare one to the other. But at the fourth company I’m apparently not me at all. Nor is the LivingDNA me related in a one-to-one comparison to my sisters or my brothers or…
Um… back to the drawing board here…
Cite/link to this post: Judy G. Russell, “When you’re not you,” The Legal Genealogist (https://www.legalgenealogist.com/blog : posted 7 Apr 2019).
SOURCES
- See generally ISOGG Wiki (https://www.isogg.org/wiki), “Autosomal DNA,” rev. 28 Jan 2019. ↩
- Which means I pay for access to special tools for DNA analysis. See Kitty Cooper, “New Utilities at GEDmatch: Tier 1 for paid members,” Kitty Cooper’s Blog, posted 20 Oct 2014 (https://blog.kittycooper.com/ : accessed 7 Apr 2019). ↩
- Yes, it’s also possible that neither has data in that particular location. ↩
- A SNP is a single-nucleotide polymorphism, the “DNA sequence variation occurring when a single nucleotide adenine (A), thymine (T), cytosine (C), or guanine (G) in the genome (or other shared sequence) differs” between two persons. ISOGG Wiki (https://www.isogg.org/wiki), “Single-nucleotide polymorphism,” rev. 30 Nov 2018. ↩
- See Helen Lockstone, “A guide to reference genome selection,” 7 March 2017, Oxford Genomics Centre (https://www.well.ox.ac.uk/ogc : accessed 7 Apr 2019). ↩
Uh… disconcerting to say the least.
I ran a comparison on Genesis between my Ancestry data and LivingDNA and there are just a few short black segments on some of the chromosomes. I do not see an entire one being black as you do.
Uh-oh.
Ummm…. has Living DNA ever launched their long-awaited matching system?
They have released bits and pieces of it. It’s still far from being full released as near as I can tell. I have one match and they removed another match that I used to have late last year. I uploaded my v3 23andMe raw data as it had the most SNPs.
Well, that would certainly account for so many of us having no matches at LivingDNA. Still fishing.
Judy: As Ann Turner says on the ISOGG Facebook group, I agree that it is likely a sample mixup at LivingDNA. I would recommend you take one of your other DNA tests, best would be 23andMe since they have the best SNP overlap, and upload that raw data to LivingDNA. Once the results are processed, you’ll see who that matches 100% with, and it will be the person your sample was mixed up with.
The problem with the sample mixup issue is that my kit does show up in the family matching to my kin, and my kin show up as matches to me. So it’s more likely the raw data file I’m being sent. So an IT issue rather than a lab issue.
Maybe I need to upload my living DNA test to see if I have the same problem. My Ancestry test and my Family Tree DNA test looked like yours. Maybe I will not be me either!
Nobody else has reported the problem. (Yet.)
Not very reassuring to those of us who have not taken the test. Guess I will wait a few years yet until they immprove them some more.
I have found another issue with Genesis and LivingDNA data. When I use the DNAGedcom Client to generate an AutoCluster from the LivingDNA kit on Genesis, it has a lot of matches having Cross Clusters, compared with an Auto Cluster from an AncestryDNA kit on Genesis. These have tight Clusters with almost all the matches in the Cluster matching other people in the Cluster. I am thinking that this may be due to imputation for the LivingDNA kit.
Hi Judy, I just did a one to one comparison on genesis between my Ftdna and LivingDna test kits, while not a perfect match, as to be expected, the tests do come up a 1.0 match. Both tests were done 2017 so on the earlier chips.
Thanks. My situation does — fortunately — seem to be a fluke…